Within the context of clinical psychology, what is meant by the concept of mindfulness?

Mindfulness refers to a state of being wherein an individual coping with intense feelings of depression or anxiety learns to focus his or her mind on the moment while exercising a constant breathing rhythm through the nose (which provides greater levels of oxygen to the brain than when breathing through the mouth). Credited with founding the concept of mindfulness, Jon Kabat-Zinn defines it as follows:

“…paying attention in a particular way: on purpose, in the present momen, and nonjudgementally.” [Cabat-Zinn, Wherever you go, there you are: Mindfulness meditation in everyday life, 1994]

Often employed in concert with yoga-inspired stretching exercises, mindfulness is a form of cognitive therapy that is intended to help individuals learn to focus and appreciate the moment, and to keep problems in the proper perspective. Many people suffering from serious physical ailments, for example, cancer, have found solace in mindfulness, as it is often practiced in a group setting and emphasizes relaxation techniques. As with most forms of cognitive therapy or psychology, it is not for everyone, but, as noted, has proven beneficial for many.